• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2012.10a
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• pp.617-625
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• 2012

Non-contact detection of internal defects in a rail using ultrasonic waves is discussed in this paper. Cracks in a rail may be a cause of a serious railway accident such as derailment if left undetected. Concurrent rail inspection method based on ultrasonic testing using piezoelectric transducers has several limitations as it should keep physical contact with the rail. This work suggests a non-contact detection of internal defects in a rail using ElectroMagnetic Acoustic Transducers (EMAT) which can produce and measure ultrasonic waves in a rail without any couplant. The EMATs for rail inspection are designed and fabricated and their working performance is verified through a series of experiments on various types of internal defects in test rails. The effect of lift-off between the transducers and the rail on the generated signals is also discussed.

• 전자공학회논문지 IE
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• v.49 no.2
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• pp.30-39
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• 2012

An effective drowsy driver detection system is needed, because the probability of accident is high for drowsy driving and its severity is high at the time of accident. However, the drowsy driver detection system that uses bio-signals or vision is difficult to be utilized due to high cost. Thus, this paper proposes a drowsy driver detection algorithm by using steering angle sensor, which is attached to the most of vehicles at no additional cost, and vehicle information such as brake switch, throttle position signal, and vehicle speed. The proposed algorithm is based on jerk criterion, which is one of drowsy driver's steering patterns. In this paper, threshold value of each variable is presented and the proposed algorithm is evaluated by using acquired vehicle data from hardware in the loop simulation (HILS) through CAN communication and MATLAB program.

• Proceedings of the KOR-KST Conference
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• 2007.05a
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• pp.375-382
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• 2007

• Journal of Korean Medicine Rehabilitation
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• v.25 no.3
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• pp.119-125
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• 2015

A chronic subdural hematoma (CSDH) is an old collection of blood and blood breakdown products between the surface of the brain and its outermost covering. We present two cases with tibia fracture caused by traffic accident progressed to chronic subdural hematoma. A 72-year-old male patient had shown signs of headache, urinary incontinence and mental storm when he has been in the hospital after 3weeks without CSDH diagnosis. And a 78-year-old male patient with mild head injury suffered from right side headache after traffic accident. We took korean medical treatments associate with tibial fracture. And we knew subdural hematoma through Brain CT. It is good report which shows CSDH can can occur from traffic accident. It requires correct diagnosis and closed observation for traffic accident patients.

• Korean Journal of Hazardous Materials
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• v.2 no.1
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• pp.31-37
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• 2014

Since the unprecedented hydrogen fluoride leak accident in 2012, there has been growing demand for customized technical information for rapid response and chemical accident management agencies including the Ministry of Environment, the National Emergency Management Agency, and the National Police Agency need more information on chemicals and accident management. In this regard, this study aims to provide reliable technical data and guidelines to initial response agencies, similar to accident management technical reports of the US and Canada. In this study, we conducted a questionnaire survey and interviews on initial response agencies like fire stations, police stations, and local governments to identify new information items for appropriate initial response and improvements of current guidelines. We also collected and reviewed the Canada's TIPS, US EPA's hydrogen fluoride documents, domestic and foreign literature on applicability tests of control chemicals, and interview data, and then produced items to be listed in the technical guidelines. In addition, to establish database of on-site technical information, we carried out applicability tests for accident control data including ① emergency shut down devide, safety guard, shut down valve, ground connection, dyke, transfer pipe, scrubber, and sensor; ② literature and field survey on distribution type and transportation/storage characteristics (container identification, valve, ground connection, etc.); ③ classification and identification of storage/transportation facilities and emergency management methodslike leak prevention, chemicals control, and cutoff or bypass of rain drainage; ④ domestic/foreign analysis methods and environmental standards including portable detection methods, test standards, and exposure limits; and ⑤ comparison/evaluation of neutralization efficiency of control chemicals on toxic substances.

• Journal of Internet Computing and Services
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• v.18 no.3
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• pp.11-17
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• 2017

To the elderly, sudden falls are one of the most frightening accidents. If an accident occurs, a prompt action has to be taken to deal with the situation. Recently, there have been a number of attempts to detect sudden falls using acceleration sensors embedded in the mobile devices, such as smart phones and wrist-bands. However, using the sensor readings only, the detection rate of the falls is around 65%. Ordinary daily activities such as running or jumping could not be well distinguished from the falls. In this paper, we describe our attempts on improving the fall-detection rate. We implemented a wrist-band fall detection module, using a three-axis acceleration sensor. With the pattern matching on the fall signal-strength frequency spectrum, in addition to the conventional signal strength measurement, we could improve the detection rate by 9% point. Furthermore, by applying two wrist-bands in the experiment, we could further improve the detection rate to 82%.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.10
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• pp.95-102
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• 2016

Pipeline is making the most use of transportation of petroleum products on the land. But due to tremendous accident or environmental disaster by oil pipeline leak or pipeline stolen, leak detection systems have been used for preventing it. Leak detection method based on negative pressure wave has been used at the long distance pipeline. But even if it has showed good leak detection quality, due to making a lot of false alarm, it has weak point that disturbs concentration to system. This study suggests algorithm and method of using volume balance to decrease false-alarm of pipeline leak detection system based on negative pressure wave.

• Proceedings of the KSRS Conference
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• 2008.10a
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• pp.368-368
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• 2008

Oil spills are a principal factor of the ocean pollution. The complicated problems involved in detecting oil spills are usually due to varying wind and sea surface condition such as ocean wave and current. The Hebei Spirit accident was happened in the west sea ($36^{\circ}$41'04" N, $126^{\circ}$03'12" E) near about 8 km distant from Tae-An, Korea on December 7, 2007. The aim of this work is to improve the detection and classification performance in order to define a more accurate training set and identifying the feature of oil spill region. This paper deals with an optimization technique for the detection and classification scheme using multi-frequency and multi-polarization SAR and optical image data sets of the oil spilled sea. The used image data are the ENVISAT ASAR WS and Radarsat-1 of C-band and ALOS PALSAR of L-band SAR data and KOMPSAT-2 optical images together with meteorological or oceanographic data. Both the theory and the experimental results obtained are discussed.

• IEMEK Journal of Embedded Systems and Applications
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• v.17 no.3
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• pp.167-175
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• 2022

With the recent expansion of electric kickboards and bicycle sharing services, more and more people use them. In addition, the rapid growth of the delivery business due to the COVID-19 has significantly increased the use of two-wheeled vehicles and personal mobility. As the accident rate increases, the rule related to the two-wheeled vehicles is changed to 'mandatory helmets for kickboards and single-person transportation' and was revised to prevent boarding itself without driver's license. In this paper, we propose a wearable smart safety equipment, called SafetyHelmet, that can keep helmet-wearing duty and lower the accident rate with the communication between helmets and mobile devices. To make this function available, we propose a safe driving assistance function by notifying the driver when an object that interferes with driving such as persons or other vehicles are detected by applying the YOLO v5 object detection algorithm. Therefore it is intended to provide a safer driving assistance by reducing the failure rate to identify dangers while driving single-person transportation.

• Proceedings of the Korean Society of Computer Information Conference
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• 2022.07a
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• pp.461-462
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• 2022

최근 지속적인 출산율의 감소와 평균수명의 증가로 인하여, 대한민국의 초고령 사회는 예상보다 훨씬 빠르게 증가하고 있다. 핵가족 형태가 보편화되며 1인 가구도 함께 늘고 있어서 홀로 사는 노인의 수 역시 증가하는 추세이다. 주거 공간에서 낙상사고와 같은 고령화 안전사고가 많이 발생하고 있다. 혼자 사는 독거노인들의 경우 사고 발생 즉시 대처가 가능한 보호자가 없다는 문제점이 있다. 본 논문에서는 MediaPipe를 이용한 낙상사고 감지 시스템을 개발한다. 먼저, 이 시스템은 MediaPipe를 이용해서 카메라를 통해 실시간으로 수신된 영상에서 사람을 인식하고, 자세 유형 분석을 통해 낙상사고 발생 여부를 판별하여 애플리케이션을 통해 보호자에게 현장 상황을 알려주는 시스템이다. 낙상사고가 발생했다면 보호자용 애플리케이션을 통해 사고 발생 알림 및 현장 사진을 보여준다. 이와 같은 기술을 활용하여 응급상황에 처한 노인을 빠르게 구조하며 독거노인의 생활안전사고 문제를 해결하는 데에 기여하고자 한다.